Valve Overview

The MOOG D661-5628C is one of many models we routinely service. Our process includes disassembly, cleaning, and reassembly using reliable components.

Experience and Warranty

We stock common wear parts in-house, so most rebuilds don’t require outside sourcing. Less waiting, faster turnaround.

Specializing in MOOG D661-5628C servo valve technology for over five decades

Frequently Asked Questions

Photos help us confirm the unit type and speed up intake. You can upload them through our quote request form.

We can often prioritize urgent jobs. Note it on your request form and we’ll let you know what’s possible.

We give you a straight assessment after inspection. If repair doesn’t make sense, we’ll let you know and discuss alternatives.

If a unit is beyond repair, we explain why and can discuss replacement or exchange options.

Even if the tag is worn off, we can often match the unit based on shape, size, and internal configuration.

Disassembly and Rebuild Procedure

We disassemble every valve, inspect it inside and out, and clean all moving parts. Components that fail inspection are swapped out before the valve is rebuilt and tested.

  • In-House Parts Sourcing: Many repairs use components sourced from our inventory of 17,000+ units.
  • Cleaning: Units go through a mineral bath, with ultrasonic cleaning used for delicate internals.
  • Seal and Gasket Replacement: Worn seals and gaskets are replaced with new components during every rebuild.
  • Final Performance Verification: After reassembly, each valve undergoes bench-testing against published performance specs.

Leak and Performance Testing

With over a dozen dedicated flow test stands and a Hagenbush proportional valve system, we verify flow curves, hysteresis, frequency response, and more. Performance reports and graphs are available for purchase on request. Our operational testing verifies consistent performance.

Technical Specifications

Every MOOG D661-5628C we service is tested under real-world conditions. Our diagnostics verify performance against published specifications. Technical diagrams and Cycle life data are available for purchase upon request.

Maintenance Tips

  • Schedule preventive maintenance intervals based on duty cycle, not just calendar time.
  • Keep hydraulic fluid clean and at proper levels for consistent valve operation.
  • Store spare MOOG D661-5628C valves in a clean, dry environment to prevent corrosion and contamination.

Start Your MOOG D661-5628C Reconditioning Process

Request pricing, availability, and turnaround for your MOOG D661-5628C. NC Servo Technology provides hands-on repair with a 1-year warranty. Contact us to request your repair.

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NC Servo Technology is an independent third-party repair facility. We are not affiliated with, endorsed by, sponsored by, or authorized by MOOG or any original equipment manufacturer (OEM), nor do we claim to be a MOOG service center. All brand names, trademarks, model numbers, and part numbers referenced on this page are the property of their respective owners and are used solely for identification and compatibility purposes.